For example, a rotary machine such as a centrifugal compressor or a turbine is provided with a casing that covers rotating bodies such as a rotary shaft and a blade set from an outer circumference side. Since an interior of the casing is exposed to a working fluid, plating is carried out on an inner surface of the casing as a measure against anticorrosion, for instance, when the working fluid is carbon dioxide
Here, such plating work is typically done by immersing the casing in a plating liquid in a plating tank. Accordingly, a plating tank that has a large volume and is appropriate for the dimensions of the casing of the rotary machine is currently required, which inevitably leads to higher costs.
Incidentally, a plating method of sending a plating liquid into an interior of a long pipe under pressure and plating an inner surface of the long pipe without using a plating tank is disclosed in Patent Literature 1.